I know you've probably been asked this a thousand times, but I have yet to find a definitive answer about UV filters...

1. Do you need one?
2. Do they degrade image quality?
3. If you buy one, does it matter if it's Hoya, B&W, Heliopan, etc.
4. What’s the best price/performance/quality between the aforementioned brands?
5. If you buy one, should you keep it on all the time as to prevent damage (dust, scratches, and accidents) to the main lens?

While we’re on the subject… what about a lens hood… most Nikon lenses come with one… am I better off leaving it on?

Again, I’ve read the forums from DCRP, ImagingResource, Dpreview, etc., and have yet to find a consistent, clear, and concise answer?

My personal opinion is that I always buy a filter, be it a UV or a Skylight 1B.

The main reason being that it protects the lens from scratches, dust etc and if I was to drop the lens, heaven forbid, at least in theory the filter would be damaged not the lens (as long as it drops front down that is!). There are some benefits to the picture quality.

I tend to buy Hoya filters, I find for me they are the best with regards to value for money.

Hi Jaspreets, I've heard a lot of enthusiasts passionately discuss this subject, with many believing the addition of an extra element in the optical path can degrade the image quality, or reduce the overall contrast.

There are of course benefits to using filters though. As PrivateOnParade points out, a filter will protect your lens, while additionally influencing tone and colour balance. It's important to note though if you are using a filter for a colour change, your digital camera's white balance could easily counteract it. So if you're using coloured or polarising filters and want a similar effect to how they worked with film, always set your white balance to Daylight.

I'd also agree with PrivateOnParade that Hoya are widely regarded as one of the better brands, but ultimately it's up to you if the protection factor is worth a possible slight drop in quality. You should try some side by side tests to see if there's any discernable difference with or without a filter.

I should mention though almost every single pro I've met doesn't use filters, but that could be more down to the casual way many treat their equipment compared to enthusiasts!

It'd be great to hear what others think about this subject. Do you use filters? If so, why, and have you ever noticed a reduction in quality?

I use Hoya Skylight 1B filters and have never had any problems with them.

4. What’s the best price/performance/quality between the aforementioned brands?

Sorry I don't know, but I know Hoya are very good quality, are easy to get hold of, are not horrendously expensive and have a good reputation.

5. If you buy one, should you keep it on all the time as to prevent damage (dust, scratches, and accidents) to the main lens?

Yes, I would say so. In fact I would say this is the main purpose in owning a UV lens, even moreso than using it to filter UV rays.

Regarding lens hoods, I don't bother using them unless I am shooting outdoors in bright sunlight. I think the point of them is that they prevent the sun shining into the lens when you don't want it to. They also make your camera look quite cool!

My 2 cents: Just use the lens hood! Naturally, you should take it off for shooting But rarely in my photographic history did I encounter a situation where the front lens got dirty while shooting. The big mess normally happens while transporting your gear.
And then: If you ruin your uv-filter and don't realize it, you certainly will have a negative impact on pic quality.
This can never happen with the lens hood